1. Field of the Invention
The present invention relates to a cleaning blade used for the purpose of scraping off the toner remaining on the peripheral surface of an image-forming body in an electro-photographic apparatus and to a process for producing the same. More particularly, the present invention pertains to a cleaning blade which is used for said purpose and has excellent performances in that the aforesaid cleaning blades is minimized in the deflection of its tip part, never contaminates an image-forming body and so forth, and to a process for producing the aforesaid cleaning blade in high efficiency.
2. Description of the Related Arts
In an electrophotographic apparatus including a copying machine, there has heretofore been generally adopted a copying method which comprises the steps of at first, uniformly electrically charging the surfaces of a photosensitive body in which is used a photoelectro conductive substance, for example, ZnO, CdS, Se, OPC (organic photoconductor) , and .alpha.-Si; projecting an image there onto from an optical system to electrically discharge the part which has been stricken by the light from the optical system, thereby forming a latent image; and subsequently carrying out adhesion of a toner (development) and transfer of the toner image to a transfer material (recording medium ) such as paper.
Since in such an electrophotographic apparatus, a toner remains on the peripheral surface of a photosensitive body (an image-forming body such as a photosensitive drum) after the transfer of a toner image, there is carried out a method in which the remaining toner is scraped and removed by bringing the tip part of a plate member 1 into sliding contact with the peripheral surface of the above-mentioned. image-forming body by the use of, for example, a cleaning blade equipped with said plate member 1 and a support member 2 as shown in FIG. 1(a) perspective view and (b) cross-sectional view.
The cleaning blade imparted with such a function is required, in general, to have the performances including that (1) the cleaning blade is minimized in deflection and is straight; (2) it never contaminates or damages the image-forming body; (3) it is excellent in wear resistance; and so forth.
In such a cleaning blade, use is usually made of Ek plate member(blade part) which comprises a thermoplastic elastomer such as urethane base elastomer, and which is produced by the use of cast molding using a mold. That is to say, a cleaning blade wherein the above-mentioned plate member and the support member are integrated, is produced by arranging a support member in a mold for the objective cleaning blade, thereafter casting a molding material for the plate member in said mold and then curing the molding material.
In order to enhance the mold release property in such cast molding using the mold, use is usually made of a mold which is subjected on the surface thereof to metallic plating containing a fluorine component. However, the foregoing cast molding involves the problem that the plate member is stuck onto the inside surface of the mold, is pulled towards both sides of the mold when it is opened, and as the result, the deflection is increased at the tip part of the plate member (that is, the tip part of the cleaning blade). As a countermeasure there against, there is taken into consideration a method in which a mold release agent is applied onto the inside surface of the mold to enhance the mold release property. Nevertheless, there is caused in this case, a fear that the mold release agent is stuck onto the surface of the plate member, thereby contaminating the image-forming body.